The Megger® TTR20 is an automatic hand-held battery operated transformer turns ratio test set.
It is used to measure the turns ratio, excitation current and polarity of windings in
single- and three-phase distribution and power transformers (tested phase by phase),
potential & current transformers, and tapped transformers.
The TTR20 offers a rugged, high-impact, shock resistant case designed to IP54, IEC1010-1, CE and ASTM D999.75. With simple one-button operation, the unit can be held in one hand... it weighs only 1.9 pounds.
While The TTR20 can test any transformer, single- or three-phase (tested phase by phase), it has been simplified to especially meet its two principle applications: distribution transformers and meter shops. Three test functions have been eliminated for easier operation, but in addition to the highest turns ratio on the market, the unit also measures excitation current and will identify normal and reverse polarity.
Furthermore, the excitation voltage range, already lowest in industry, has been expanded with the addition of a 0.5 V test. This further facilitates the determination of no-load accuracies for CTs and PTs, making the unit the ideal choice for meter shop applications. Ratio errors for bushing CTs can be measured to an accuracy of ±0.1% nameplate.
Four-termination test leads simplify hook-up and speed testing, with measuring time less than 5 seconds. With no need to store complex hookup patterns for its core applications, memory has been eliminated. However, test results can be sent to a printer, as well as viewed on a backlit display.
For full-service customers, the added measurements (phase displacement, vector group, winding resistance) and storage capabilities afforded by TTR100 are highly desirable. For simpler applications, TTR20 is the enhanced model in terms of ready performance.